Effective treatment of wastewater (WW) and its reuse is necessary to meet certain sustainable development goals and a circular economy. Escherichia coli is one of the primary contaminants in the WW, and its extra-intestinal occurrence poses a considerable threat under one health. This study is the first report of a novel broad-spectrum phage (фERS-1) isolated from a pristine stretch of the Ganges River in the biocontrol of E. coli, resistant to 3rd-and 4th generation cephalosporins and aztreonam. This is the first report of a phage from the Tequatrovirus genus to infect P. aeruginosa. The фERS-1 could reduce the abundance of E. coli cells by 8.22 log10 CFU/mL ≤24 hrs. Additionally, ɸ ERS-1 disrupted the biofilm of E. coli with a reduction of 3.88 log10 CFU/mL. Further, ɸ ERS-1 could inhibit biofilm by multiple strains of E. coli and multiple genera (E. coli, S. boydii, and P. aeruginosa). The phage ɸ ERS-1 reduced bacterial counts in raw WW by 2 log10 CFU/mL and 4 log10 CFU/mL reduction in coliform-enriched WW in ≤24 hours. Overall, this study suggests that ɸ ERS-1 could be used as an effective alternative to be combined with other treatments for improving the quality of WW disposal and environmental health by reducing the bacterial load.